Most of the antimony trisulfide available on the market is produced by processing natural antimony trisulfide ore (stibnite). Specifically, when natural antimony trisulfide ore is melted, antimony trisulfide precipitates, while impurities such as gangue float up. Antimony trisulfide can thus be collected.
Antimony trisulfide can also be produced by mixing an antimony metal powder and sulfur, and calcining the mixture. Antimony metal can be produced using the method disclosed in JP-A-6-322455, for example.
It is also possible to collect antimony trisulfide that precipitates when antimony trioxide is added to a sodium sulfide solution, and hydrogen sulfide is passed through the solution. Antimony trioxide can be obtained by volatilization-oxidation refining disclosed in JP-A-6-329417, for example. Antimony trioxide is abundantly available on the market as a fine powder.